<div class="sortable-container">

    <div id="example3">

        <div style="min-height: 50px; min-height:50px; height:auto !important;">
            <style type="text/css" media="screen">
                #placeholderSortable li {
                    float: left;
                }
            </style>
            <ul id="placeholderSortable" style="list-style-position: inside; height: 30px; cursor: hand; cursor: pointer;">
                <li id='user_Jack'>Jack</li>
                <li id='user_John'>John</li>
                <li id='user_Marry'>Marry</li>
                <li id='user_Claire'>Claire</li>
                <li id='user_Daniel'>Daniel</li>
            </ul>

        </div>

    </div>

</div>